Electric battery and process for manufacturing battery cells



June 12, 1928,. r

H; M. R. DAM

ELECTRIC BATTERY AND PROCESS FOR MANUFAGTURINGBATTERY CELLS Filed May 1; 1925 4 Sheets-Sheet 1 WM m.

INVENTOR ATTORNEYS.

June 12,1928. 1,673,402

H. M. R. DAM

ELECTRIC BATTERY AND PROCESS FOR MANUFACTURING BATTERY CELLS Filed May 1, 1925 4 Sheets-Sheet 2 1.0 7 1 7 I 6 in INVENTOR W BY ATI'ORNEYJi June 12, 1928.

- H. M. R. DAM

ELECTRIC BATTERY AND PROCESS FOR MANUFACTURING BATTERY CELLS Filed May 1, lzs 4 Shets-She 5 INVENTOR I ATTORNEYS.

June 12, 1928. 1,673,402

H. M. R. DAM

ELECTRIC BATTERY' AND PROCESS FOR MANUFACTURING BATTERY CELLS Filed May 1925 4 Sheets-Sheet 4 1 49 *46 /14' I I I l 47 48 as 11' 59 A 49 44 M12 1 5] M l, N

0'! v v 50' INVENTOR Y BY ATTORNEYS v Patented June 12, 1928.

UNITED STA TES PATENT OFFICE;

HENRY BOSEJSIDAIIZ. DAM, OF ASTORIA, NEW YORK, ASSIGNOR TO PBEHO ELECTRIC CORPORATION. ACORIPORA'IION OF NEW YORK.

ELECTRIC BATTERY Ann zenocnss roe MANUFACTURING BATTERY came Application filed Kay 1, 1925';- Serial No. 27,183.

' I invention relates to electric batteries of the. flat cell type and to a process for manufacturing the cells entering into the bat;

tery. An important object of the invention is to provide a generally improved battery of the character mentioned together with an im-' through a die so constructed as to produce proved process for facilitating the manufacture of the cells entering into the battery structure.

A further object of the invention is to ro-' the following description when taken in con nection "with the accompanying drawings in which-- v I Figure 1 is a plan view of a mold adapted to be used in carryingout the process with the zincplate and an insulating frame in position therein. a

Figure 2 is a transverse sectional View taken on line 2-2 of Figure 1, showing in section'the zinc plate, insulating frame and electrolyte-paste-covered pulp board.

Figure 3 is a similar view showin the depolarizing mix as having been introduced into the mold and scraped off flush with the top thereof. f 1 Figure 4 is a similar view showing a quantity of graphite as having been introduced into the mold subsequent to the compression of the depolarizing mixture.

Figure 5 is a similar view showing a metallic layer of materiaLsuch as tin foi having been placed in position upon the layer of graphite prior to final compression.

Figure 6 is a vsimilar view showing the graphite with the layer of tin foil as having been subjected to final compression in completing the formation of a cell embodying my invention.

Figure 7 is a transverse sectional view through a die similar to that shown in Figures l to 6 but of such-dimensions as to receive a cell of the type shown in Figure 6 upon which an identical cell is adapted to be formed, and shows at its lower part a cell such as is shown in Figure'6 in in verted osition and completely formed upon it anot er similar cell.

Figure 8 is a perspective view of two cells constructed and united in accordance with the disclosure of Figure 7.

Figure 9 is a view similar to Figure 8' but showing also a container for the batigu're 10 is a: transverse sectional view Figure 13 is a view similar to Figure 12. I

showing the several cells arranged within a suitable container and urged into an intimate face to face relation by means of wedging devices. y

In thedrawings wherein for the purposes of illustration are shown certain apparatus for carrying out the several steps incident to the process embodying the invention and wherein are also shown certain modified forms of cells and batteries embodyin the T invention, the numeral 5 indicates a 1e or mold comprising a base plate 6, havin raised portion 7 around which is adapte to be placed a chase 8 which is cut awa as shown at 9 to provide a pocket adapte for the reception of a wing 10 of a zinc plate 11 which constitutes a negative electrode common to the .two cells hereinafter more particularly described entering into the structure shown in Figures 7 to 9, inclusive.

It will be noted that the chase 8 is provided with a shouldered flange 12 which forms with the upper face of the raised ortion 7 of the die a recess 13 into whic a frame 14.0f angular cross-section and con-' structed from a suitable insulating material, such as cardboard, is adapted to be fitted when placed upon the zinc plate 11. This frame may be impregnated or coatedw'ith asuitable material, such as parafiin in order to render the same impervious to moisture.

It has a horizontal flange 15 adapted to rest and zinc plate 11 within the die, a suitable carrier, such as a pulp board 16, carrying the pulp board in posiange 15 asuitable quantity of depolarizing mixture 17', cons1sting, for example, of sultable proportions of manganese, graphite and sal ammomac, is'mtroduced into the chase 8. The depolarizing mixture is. upon being introduced into the chase 8,-piled up above the upper face of the chase then scraped off level and subjected to compression by a plunger or die member 18, ada ted to enter the chase 8. The plunger 18 see Fig. 3), upon entering the chase 8, depresses the depolarizing lIllX- ture to a lower level for example, such as is shown in Figures 4 and 5, ormlng the depolarizingmixture into a relatively comact mass. As a result of the depolarlzmg mixture havin been compressed, a sufficient space is a orded at the top of this material, upon removing the plunger 18, to accomodate a quantity of graphlte which is introduced into the chase 8 and spread over the surface of the depolarizing mix to form a graphite layer 19, the upper surface of which lies flush with the upper surface of the chase 8. In preparmg the graphite a suitable quantity of wax is mixed with it, after which the mixture is ground into owdered form, the wax being equally distributed .with respect to the graphite and serving to render the graphite mass 1mpervious to moisture after compression, as will be readily understood.

After the layer of graphite has been introduced into the die as shown in Figure 4 this layer is heated, as by means of a blowtorch, for the purpose of softening the wax in order to render the mass more or less plastic, thus enabling it to readily respond to the compression force to be subsequently exerted upon it. After heating the layer of graphite, a metallic facing such, for example, as tin foil 20 is placed upon the graphite layer as shown in Figure 5. With the tin foilso positioned the depolarizing mix, graphite layer and tin foil are collectively subjected to compression by means of a second plunger or die" member 21. The lower or compression face of this plunger is provided with a plurality of lobes and pockets 22 and 23, respectively, in order to form a plurality of depressions and protuberances 22'v and 23', respectively, in the face of the graphite layer, which layer becomes, as a result of the compression,

a compact mass adapted to be utilized as the positive element of a cell. Inasmuch as the metallic facing 20 assumes a contour corresponding to the contour of the face of the graphite element, a relatively large surface contact is provided between the metallic facing and the graphite. Not only isa relatively large contact area thus afforded between the metallic facing 20 and the graphite, which results in a minimum resistance to an electric current flowing from one of these elements to the other, but, by reason of the fact that the tin foil conforms to the irregular face of the graphite element, a highly effective physical union is established between the contacting surfaces of these elements.

Inasmuch as the pulp board 16, carrying the electrolyte on both faces, is relatively pliant it is distorted from its position shown, in Figure 2 and forced into intimate contact, substantially throughout its entire area, with the zinc plate 11 as shown in Figures 3 to 7, inclusive, upon initial com-, pression of the depolarizing mixture. In subjecting the graphite layer 20 to compression the depolarizing mixture is incidentally subjected to final compression and forced to the level shown in Figure 6, the pulp board 16 being at the same time urged into further intimate contact with the zinc plate 11.

Since the depolarizing mix 17 and the graphite layer 19 are more or less plastic or yieldable under the influence of final compression, the line of initial jointure intermediate the depolarizing mix and graphite is distorted, due to possible variations in mass density of the depolarizing mix and graphite, from a straight line contact, shown in Figures 4 and 5, to an irregular contact as indicated by the undulatory line of demarcation 24 in Figure 6. The irregular surface produced between contacting faces of the'depolarizing mass and raphite element, as will be readily un crstood. serves to provide for a more intimate and permanent keying engagement between the graphite and the depolarizing mass than if these two materials were united on a straight plane such as exists between the depolarizing mass and graphite layer at the outset of the final compression.

Upon completion of the'final compression the cell comprising the zinc plate or negative electrode 11, the frame 14. the pulp board 16 functioning as a vehicle for the electrolyte, the depolarizing material 17', the layer of graphite 19, compressed to provide the positive electrode of the cell, and the metallic layer 20, may be readily removed as a compact and intimately united structure upon which a second cell, utilizing the zinc plate of the first cell as a negative electrode, may be formed as will now be described.

In carrying the process further into effect,

a complete cell such as is shown in Figure 6 and indicated as a whole by the numeral 25,

is placed in inverted position, with the zinc plate or electrode 11 uppermost, upon the upper face of the raised portion 7 of the base plate 6, as shown in Figure 7, whereupon a second chase 8, containing a second insulated frame 26, is placed upon the base plate 6 in the position shown in Figure 7. This chase 8' is substantially identical with the chase 8, hereinbefore described, except that it is of such a thickness asto form a recess till on both'faces with an electrolytic paste 27 is introduced into the chase 8'. After properly positioning the pulp board 27 within the chase 8', the depolarizing mixture 17 is introduced into the mold and compressed as previously described in the formation of the cell 25. After compressing the depolarizing mixture 17 a quantity of graphite 19 is introduced into the chase 8' and this graph ite is subjected to heat, such as of a blow torch, for the purpose previously described. Subsequent to heating the graphite layer a metallic facing such as tinfoil 20 is applied thereto whereupon the graphite layer 19 is subjected to compression by means of the die.

member 21. As a result of this compression the gra hite layer 19 is compressed into a relative y compact mass adapted to function as a positive electrode having depressions and protuberances 22' and 23', respectively,

; formed upon its face.

As a result of the successive steps carried out subsequent to the completion of the first cell 25, a second cell 28 is formed, the cell 28 being substantially identical with the cell 25 and the several steps incident to the produc tionof the same being substantially identical with the respective corresponding steps employed informing the cell 25.

Upon completion of the cell 28 the two cells shown in Figure 7 may be removed from the chase 8' as a unitary structube in which the zinc plate 11 functions as a negative electrode common to the two cells. The outer margin of the battery as thus far completed, is next dipped into wax in order to seal the several joints and thereby render the struc tnre airtight and moisture-proof. It will be noted from Figure 9 that the film of wax 29 extends over 'the faces of the graphite layers 19 only a relatively short distance leaving a relatively large area of the metallic facing exposed. llpon the top of the battery there is ositioned strips of flat and corrugated cardoard 30, preferabl impregnated or coated with. paraffin, and eing split, as shown at 31, to receive the projecting wing mt the zinc plate, to which wing a suitable binding post 32 is connected. After positioning the strips of cardboard 30 as shown, a metallic yoke' 33, provided with a terminal 35, is placed upon the battery with its legs, one of which is indicated by the numeral 34, in contact with the'metallic facings 20, thereby electrically connecting, the positive electrodes of the battery to eachother. After positioning the yoke 33 as shown, cardboard facings 36, preferably impregnated or coated with. wax, are applied to opposite sides of the battery and the battery is the introduced into a suitable cardboard container 37 and seated upon a cardboard spacer 38. A suitable sealing material, such as wax or pitch 39, is then poured around the battery,

filling the space afforded between the battery and the wall ofthe container. This sealing material functions to reinforce the battery, in its entirety, and to further render 'the same airtight and impervious to'moisture. After introducing the sealing materials 39, as described, the battery is finally sealed in accordance with usual practice by pouring over the top of the same a quantity of sealmg wax. r-

In constructing the modified form of cell shown in Figures 10 to 13, inclusive, the several steps corresponding to the steps employed in constructing the cell 25 are carried out, that is to say, the zinc plate 11 is positioned within'a mold 4 1, as shown in resting upon the zinc plate 11'. After positioning the zinc plate 11' and the cardboard frame 14' as shown, a pulpboard 38, carrying a suitable quantity of moisture and covered on both sides with suitable electrolytic paste, is introduced and upon this pulp board is formed a layer of compressed depolarizing -mixture 39. After compressing the depolarizing mixture a quantity of powdered graphite 40, into which may be incorporated a suitable quantity of wax, is in- .troduced into the mold and thereafter subjected to compression .by a plunger or die member 42. This plunger or die member, however, is cut out to Figure 10, with the cardboard frame 14 1 provide a pocket 43,

as a result of which the compressed graphite 40, which functions as the positive electrode of thecell, is provided with a protruding portion 4i adapted to contact with the zinc plate 11' which is the negative electrode of the adjacent cell when the several cells are positioned in a face to face relation as shown in Figure 12. In order to render the graphite 40 more or less plastic so as to enable it to respond to the action of the die member 42 the graphite may be subjected to heat, such as of a'blow torch. A metallic facing such as tin foil 45 may then be placed upon the graphite and united therewith upon the application of pressure by the die member 42. If desired, the die member 42 may be provided with depressions and protuberances identical with those disclosed in Figure 6, and hereinbefore described, for the purpose of increasing the contact area between the graphite and tin foil and for the urpose also of effecting an intimate physical union between these two elements.

From the description of the modified form of cell, shown in Figures 10 to 13, inclusive, it will be apparent that the method of constructing such cell is identical with the process herc nbefore described in connection with Figures 1 to 6, inclusive, and that the form of cell shown in Figures 10 to 13, inclusive, is substantially identical with the form of cell indicated by the numeral except, however, that the positive electrode is provided with a protruding portion and the negative electrode or zinc plate 11' overlies or projects beyond the cardboard frame 14 ification in the upper an an a ppreciable distance instead of terminating flush therewith. Inasmuch as the zinc plate 11 or negative electrode projects beyond or overlies the frame 14 a slight modlower sections 46 and 47 of the die 41 is necessitated, the sec tion 41 being undercut as shown at 48 to receive the'plate and the raised portion 49 of the lower section.

After the cell has been formed it may be removed from the mold 41, as a unit, and coated around its margin or edge with parafiin to provide a film 49' similar to the film indicated by the numeral 29 in Figure 9.

Prior to introducing the cells into a suitable container, such as is indicated by the numeral 50, each may be provided with a strip of corrugated board 51 extending entirely around the same. After introducing the cells into the container 50 in an end to end relation with the positive electrode of, each cell abutting the negative electrode of the adjacent cell suitable wedges, such as are indicated by the numeral 52, are .introduced into the container at opposite ends thereof. These wedges are employed for the purpose of urging the cells into intimate face to ,face engagement with each other. Before introducing the wedges 52, however, contact strips 53 and 54, carrying terminals 55 and 56 are placed respectively in contact with the zinc electrode of the cell at one. end of the battery and in contact with the posi: tive electrode of the cell at the opposite en of the battery. These contact strips under the influence of the wedging action of the wedge 52 are urged into intimate engagement with the opposed electrodes of the battery. After assembling the cells in an end to end relation within the container 50 and urging them into intimate engagement with sealing material such is poured around the cells and a strip of cardboard 57, or other insulating material, is then positioned as shown upon the upper edges of the zinc plates 11. Upon this strip of cardboard is poured a quantity of suitable sealing material such as wax 58 which functions as a means for sealing the battery thus rendering the same impervious to moisture.

' Certain advantages are to be derived from a battery made up of a plurality of cells of the type shown herein but claimed in my copending application Serial No. 27,134, filed May .1, 1925, in each of which cells the electrolyte is applied to both sides of the carrier such as pulp board, rather than upon only that side of the carrier adjacent the negative electrode as has heretofore been customary. One advantage is a material increasein ampere hour capacity. Another advantage is the materal reduction in internal resistance offered within each cell. A further advantage resides in the fact that the batte immediately delivers its rated voltage a er a relatively long period of inactivity.

Having thus described my invention I claim:

1. The process of producing a battery cell which consists in compressing a quantity of depolarizing mixture upon a negative electrode with intervening electrolyte so as to unite the electrode and depolarizing mixture, and compressing a quantity of positive electrode-forming material upon the depolarizing mixture, thereby forming a positive electrode and simultaneously. uniting the same with the depolarizing mixture.

2. The process of producing a battery cell which consists'incompressing a quantity of depolarizing mixture upon a negative electrode with intervening electrolyte so as to unite the electrode and depolarizing mixture, superimposing u on the depolarizing mixture a quantit 0 positive electrode-forming material, app ying a metallic facing to the positive electrode-forming material, and compressing said positive electrode-formin material upon the depolarizing mixture, tierehy forming a positive electrode and simultaneously uniting the same with the depolar- 1Z1Ilg mixture and said facing.

each other a suitable as wax or pitch 50 3. The process of producing a battery cell which consists in applying to a negative electrode a carrier coated with an electrolyte, superimposing upon the carrier a quantity. of depolarizing mixture, compressing the ded polarizing mixture into cake form thereby uniting the same together with the electrolyte and negative electrode into a unitary structure, superimposing upon the depolarizing mixture 9. quantity of positive electrode-forming material, and compressing the positive electrode-forming material thereby forming a positive electrode and simultatrode and simultaneously uniting the same,

with the depolarizng mixture and said facing.

5. The process of producing a battery cell which consists in applying to a negative electrode a carrier provided with an electrolyte, s perimposing upon the carrier a quantity of I epolarizing mixture, compressing the depolarizing mixture into cake form and simultaneously uniting the same with the negative electrode and electrolyte in a unitary structure, superimposing upon the depolarizing mixture a quantity of carbonaceous material having an impregnating substance mixed therewith, subjecting 'the carbonaceous material to heat, superimposing upon the carbonaceous materiala metallic conductor, and subjecting the conductor, carbonaceous material, and depolarizing mixture to pressure whereby the conductor, carbonaceous material, depolarizin mixture, negative electrode, carrier an electrolyte are united in a unitary structure.

'6. The process of producing a battery cell which consists in applying a frame of insulating material to a negative electrode, applying to the negative electrode an electrolyte, introducing into the frame a quantity' of depolarizing mixture, subjecting the depolarizing mixture to pressure to produce a cake of such material and physically unite the mixture to the negative electrode,

superimposing upon the depolarizing mixture a quantity of positive electrode-forming material, and sub ecting the positive electrode-forming material to pressure to reduce the positive electrode-forming material to cake form and physically unite the same to said depolarizing mixture whereby said negative electrode, electrolyte, frame, depolarizmaterial are united into a unitar structure.

7. The process of producing a attery cell which consists in applying to a negative electrode a frame, introducing into the frame a carrier coated with an electrolyte, intr0-' ducing into the frame a quantity of depolarizing mixture, subjecting the depolarizing mixture to pressure to produce a cake of such mixture and unite the same with said negative electrode, carrier, electrolyte and frame as a unitary structure, introducing into the frame a quantity of carbonaceous material, and subjecting the carbonaceous material to pressure to produce a positive electrode and physically unite the same with said depolarizing mixture.

8. The process of producing a battery cell which consists in applying to a negative electrode a frame, introducing into the frame a carrier coated with an electrolyte, introducing into the frame aquantity of depolarizing mixture, subjecting the depolarizing mixture to pressure to produce acake of such mixture and unite the same with said negative electrode, carrier, electrolyte and frame as a unitary structure, introducing into the frame a quantity of carbonaceous material, subjecting the carbonaceous material to heat, superimposing upon the carbonaceous material a metallic conductor, and subjecting the conductor and carbonaceous material to pressure to produce a positive electrode in cake form and physically unite the same with said depolarizing mixture and to simultaneously physically unite the metallic conductor to said positive electrode.

9. A battery comprising a negative electrode, a frame of insulating material carried upon each face of said electrode, depolarizing mixture carried within said frames upon opposite sides of said electrode, carbonaceous material carried upon said de olarizing mixture at opposite sides of sai negative electrode and constituting positive electrodes of the battery, and a carrier arranged u h opposite faces of said negative electro e, each of said carriers being provided upon opposite sides with an electrolyte.

In testimony whereof, I have aflixed my signature to this specification.

HENRY M. ROSENDAL DAM.

mg mixture, and positlve electrode-forming 

